We fabricated three crosslinked

porphyrin-based polyimides (PPBPI-CRs) from PEPHQDA, TAPP and three terminal anhydrides (PA,

PEPA and PENA) via alkynyl groups crosslinking

reactions. PPBPI-CRs had permanent porosities and

revealed outstanding thermal stabilities. Affected by π-stacking

and molecular sizes effect, with increasing conjugate and molecular sizes

effect in different terminal anhydrides, porphyrin-based polyimides (PPBPIs) revealed

decreased specific surface areas (106.8 – 8.3 m2 g-1),

whereas, PPBPI-CRs showed increased BET surface areas (1.8

- 633 m2 g-1). Meanwhile, PPBPI-CRs had considerable CO2 uptakes (1.37,

2.01 and 2.37 mmol g-1) and isosteric heats of CO2

adsorption (34.8, 27.5 and 22.6 kJ/mol). The PPBPI-CRs had CO2/N2 (39.83, 36.95,

40.08) and CO2/CH4 (14.13, 9.78, 10.87) separation selectivities.